| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package filter_impl |
| |
| import ( |
| "context" |
| "time" |
| ) |
| |
| import ( |
| "github.com/apache/dubbo-go/common/extension" |
| "github.com/apache/dubbo-go/config" |
| "github.com/apache/dubbo-go/filter" |
| "github.com/apache/dubbo-go/metrics" |
| "github.com/apache/dubbo-go/protocol" |
| ) |
| |
| const ( |
| metricFilterName = "metrics" |
| ) |
| |
| var ( |
| metricFilterInstance filter.Filter |
| ) |
| |
| // must initialized before using the filter and after loading configuration |
| func init() { |
| extension.SetFilter(metricFilterName, newMetricsFilter) |
| } |
| |
| // metricFilter will calculate the invocation's duration and the report to the reporters |
| // If you want to use this filter to collect the metrics, |
| // Adding this into your configuration file, like: |
| // filter: "metrics" |
| // metrics: |
| // reporter: |
| // - "your reporter" # here you should specify the reporter, for example 'prometheus' |
| // more info please take a look at dubbo-samples projects |
| type metricsFilter struct { |
| reporters []metrics.Reporter |
| } |
| |
| // Invoke collect the duration of invocation and then report the duration by using goroutine |
| func (p *metricsFilter) Invoke(ctx context.Context, invoker protocol.Invoker, invocation protocol.Invocation) protocol.Result { |
| start := time.Now() |
| res := invoker.Invoke(ctx, invocation) |
| end := time.Now() |
| duration := end.Sub(start) |
| go func() { |
| for _, reporter := range p.reporters { |
| reporter.Report(ctx, invoker, invocation, duration, res) |
| } |
| }() |
| return res |
| } |
| |
| // OnResponse do nothing and return the result |
| func (p *metricsFilter) OnResponse(ctx context.Context, res protocol.Result, invoker protocol.Invoker, invocation protocol.Invocation) protocol.Result { |
| return res |
| } |
| |
| // newMetricsFilter the metricsFilter is singleton. |
| // it's lazy initialization |
| // make sure that the configuration had been loaded before invoking this method. |
| func newMetricsFilter() filter.Filter { |
| if metricFilterInstance == nil { |
| reporterNames := config.GetMetricConfig().Reporters |
| reporters := make([]metrics.Reporter, 0, len(reporterNames)) |
| for _, name := range reporterNames { |
| reporters = append(reporters, extension.GetMetricReporter(name)) |
| } |
| metricFilterInstance = &metricsFilter{ |
| reporters: reporters, |
| } |
| } |
| |
| return metricFilterInstance |
| } |